Membrane
Biochemistry

Biological membranes form the barriers which separate cells from their
environments, and allow compartmentalization within cells. Our main research
interest is to understand how proteins and lipids interact to regulate
membrane structure and function. Protein-lipid interactions are important
in biological processes, such as; exocytosis, endocytosis, regulating
the activity of membrane proteins, cell division, neurotransmitter release,
and organelle biogenesis.

Some of our research questions are:

how do lipids influence structure and dynamics of membrane proteins?

how do lipids affect the insertion of proteins into membranes?

how do lipids regulate the activity of membrane proteins?

how do proteins affect the structure and dynamics of lipids?

how do peripheral membrane proteins affect the lateral distribution
of lipids in the membrane?

We are trying to understand the physicochemical behavior of proteins
and lipids in membranes. For example, we have found that the binding of
the synaptic vesicle protein, synapsin I
is modulated by the lipid packing within membranes. Cells can control
the lipid packing in their membranes by metabolically altering the lipid
composition and cholesterol levels. We use a variety of modern approaches that bridge biophysics, biochemistry,
molecular biology and bioinformatics. Included are cloning and expression
technologies that involve site-directed mutagenesis and recombinant protein
purification and characterization as well as model membrane production
and characterization. Biophysical techniques which are employed in our
research include fluorescence spectroscopy,
liposome production, isothermal
titration calorimetry (ITC), atomic force microscopy
(AFM), near-field microscopy and various types of chromatography. Through such studies, we are obtaining a better understanding
of the physicochemical parameters that affect the interaction of proteins
with membranes.